How to restore steel frame rigidity

ben5020
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ben5020
It seems as though when steel frame bike hit higher hours the bike flexes or moves more, is there anyway other then gusseting the frame to revive it so you speak? Does heat treating steel frames do anything like it does to aluminum? Steel stretches so I’ve been told and it sure would be nice to have that new feel when the hours get up there. Any and all help is greatly appreciated.
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Richy
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Richy 7/11/2022 1:47pm
7/11/2022 1:47pm
Most high end steel BMX frames are heat treated when new, and most are the same chromoly steel as steel Motocross frames as far as I know, though I'm happy to be corrected.

As far as heat treating a used frame, that has presumably already been heat treated when new, I'm not sure how that would shake out.

What I've always meant to ask and will tack onto this topic, welding repairs to heat treated steel frames... What's the deal with this?
Lasse
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Lasse 7/11/2022 1:52pm
7/11/2022 1:52pm
ben5020 wrote:
It seems as though when steel frame bike hit higher hours the bike flexes or moves more, is there anyway other then gusseting the frame to...
It seems as though when steel frame bike hit higher hours the bike flexes or moves more, is there anyway other then gusseting the frame to revive it so you speak? Does heat treating steel frames do anything like it does to aluminum? Steel stretches so I’ve been told and it sure would be nice to have that new feel when the hours get up there. Any and all help is greatly appreciated.
Steel does not loose its stiffness over time. If it feels loose, what comes to mind is your bearings in the chassis.
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Big Lenny
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Big Lenny 7/11/2022 1:54pm
7/11/2022 1:54pm
ben5020 wrote:
It seems as though when steel frame bike hit higher hours the bike flexes or moves more, is there anyway other then gusseting the frame to...
It seems as though when steel frame bike hit higher hours the bike flexes or moves more, is there anyway other then gusseting the frame to revive it so you speak? Does heat treating steel frames do anything like it does to aluminum? Steel stretches so I’ve been told and it sure would be nice to have that new feel when the hours get up there. Any and all help is greatly appreciated.
Lasse wrote:
Steel does not loose its stiffness over time. If it feels loose, what comes to mind is your bearings in the chassis.
RC..James..and Barnett all stretched frames...
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ben5020
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ben5020 7/11/2022 1:58pm
7/11/2022 1:58pm
Richy wrote:
Most high end steel BMX frames are heat treated when new, and most are the same chromoly steel as steel Motocross frames as far as I...
Most high end steel BMX frames are heat treated when new, and most are the same chromoly steel as steel Motocross frames as far as I know, though I'm happy to be corrected.

As far as heat treating a used frame, that has presumably already been heat treated when new, I'm not sure how that would shake out.

What I've always meant to ask and will tack onto this topic, welding repairs to heat treated steel frames... What's the deal with this?
I know aluminum needs to be heat treated after welding to restore its metallurgy or whatever the word is 🤣 atleast bbr repaired an aluminum pitbike frame fire me and had it heat treated after welding the engine mount, not sure if steel would need it or not
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Cygrace74
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Cygrace74 7/11/2022 2:13pm
7/11/2022 2:13pm
Lasse wrote:
Steel does not loose its stiffness over time. If it feels loose, what comes to mind is your bearings in the chassis.
Tell that to anyone with an old two stroke snapping motor mounts constantly
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Rickyisms
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Rickyisms 7/11/2022 3:21pm
7/11/2022 3:21pm
Cygrace74 wrote:
Tell that to anyone with an old two stroke snapping motor mounts constantly
It doesn't have to be old! I have a friend who is pretty fast on a 125 (Qualified for schoolboy 1 a couple years ago when he still raced) and has had to reweld his old 2018 KTM with less than 100 hours multiple times and in multiple spots, pretty sure it was on weld job #8 last time I saw him.
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McG194
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McG194 7/11/2022 6:56pm
7/11/2022 6:56pm
ben5020 wrote:
It seems as though when steel frame bike hit higher hours the bike flexes or moves more, is there anyway other then gusseting the frame to...
It seems as though when steel frame bike hit higher hours the bike flexes or moves more, is there anyway other then gusseting the frame to revive it so you speak? Does heat treating steel frames do anything like it does to aluminum? Steel stretches so I’ve been told and it sure would be nice to have that new feel when the hours get up there. Any and all help is greatly appreciated.
Lasse wrote:
Steel does not loose its stiffness over time. If it feels loose, what comes to mind is your bearings in the chassis.
On a molecular level there is a lot going on in your steel frame. Rather than taking a bunch of engineering courses read this. lol

https://en.wikipedia.org/wiki/Plasticity_(physics)
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kb228
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kb228 7/11/2022 7:20pm
7/11/2022 7:20pm
ben5020 wrote:
It seems as though when steel frame bike hit higher hours the bike flexes or moves more, is there anyway other then gusseting the frame to...
It seems as though when steel frame bike hit higher hours the bike flexes or moves more, is there anyway other then gusseting the frame to revive it so you speak? Does heat treating steel frames do anything like it does to aluminum? Steel stretches so I’ve been told and it sure would be nice to have that new feel when the hours get up there. Any and all help is greatly appreciated.
Lasse wrote:
Steel does not loose its stiffness over time. If it feels loose, what comes to mind is your bearings in the chassis.
All materials fatigue homie
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Luxon MX
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Luxon MX 7/11/2022 7:55pm
7/11/2022 7:55pm
A few in here are confusing stiffness with strength... Steel does NOT lose it's stiffness over time (any noticeable amount, anyway). Strength is a little different. Fatigue can set in in the high stress areas reducing the life of the frame at those points. Any part of the frame that has cracked or yielded (e.g. plasticly deformed), has done so because of a strength issue (and not necessarily fatigue related).
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